Large-particle (FLIC) method, presented in 1960’s, is a numerical method that be applied to solve unsteady flow. The computational scheme consists of two steps for each timemarch step: First, intermediate values are ...
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Large-particle (FLIC) method, presented in 1960’s, is a numerical method that be applied to solve unsteady flow. The computational scheme consists of two steps for each timemarch step: First, intermediate values are calculated for the velocities and energy, takinginto account the effects of acceleration caused by pressure gradients; Second transport effects are calculated. In this paper, we present a high resolution large-particle finite volumemethod for 2-D unstructured triangular mesh, the key idea of this method is monotonereconstruction of flow variables and solve "Riemann" problem in the first step. Finallythe result of the computation is
In this paper, we review some recent developments on the study of implicitly defined curves and surfaces in the field of computer aided geometric design(CAGD), includ-ing mainly the research on the problems of paramet...
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In this paper, we review some recent developments on the study of implicitly defined curves and surfaces in the field of computer aided geometric design(CAGD), includ-ing mainly the research on the problems of parametrization, regularity and splines of algebraic curves and surfaces.
The generalized Stein-Rosenberg type theorem is established for the parallel decomposition-type accelerated overrelaxation method (PDAOR-method) for solving the large scale block systems of linear equations. This ther...
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The generalized Stein-Rosenberg type theorem is established for the parallel decomposition-type accelerated overrelaxation method (PDAOR-method) for solving the large scale block systems of linear equations. This thereby affords reliable criterions for judging the convergence and divergence, as well as the convergence rate and divergence rate, of this PDAOR-method.
In this paper, we study the acoustic impedance inversion of 1-dimensional wave equation excited by a wavelet. In order to avoid the ill-posedness, a stable method,which we call the characteristic band method, is const...
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In this paper, we study the acoustic impedance inversion of 1-dimensional wave equation excited by a wavelet. In order to avoid the ill-posedness, a stable method,which we call the characteristic band method, is constructed, and then used as the preconditioner in optimal inversion to increase the speed of convergence.
In this paper,we discuss a Schwarz alternating method for a kind of unboundeddomains, which can be decomposed into a bounded domain and a half-planar domain. Finite Element Method and Natural Boudary Reduction are use...
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In this paper,we discuss a Schwarz alternating method for a kind of unboundeddomains, which can be decomposed into a bounded domain and a half-planar domain. Finite Element Method and Natural Boudary Reduction are used alternatively. The uniform geometric convergence of both continuous and discrete problems is proved. The theoretical results as well as the numerical examples show thatthe convergence rate of this discrete Schwarz iteration is independent of the finiteelement mesh size, but dependent on the overlapping degree of subdomains.
The incompressible Navier-Stokes (INS) equations upon discretization on fixed meshes become a system of differential algebraic equations (DAE) of index 2. It is proved in this paper that for the general explicit and i...
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The incompressible Navier-Stokes (INS) equations upon discretization on fixed meshes become a system of differential algebraic equations (DAE) of index 2. It is proved in this paper that for the general explicit and implicit Runge-Kutta (RK)methods, the time accuracy of velocity is the same as that for the ordinary differential equations, by taking into consideration of the special form of the resulting DAE; (the time accuracy of pressure can be lower). For the three-stage secondorder explicit RK method, algorithms with less (than three) Poisson solutions of pressure are proposed and verified by numerical experiments. However, in practical computation of complex flows it is found that the method must satisfy the so-called consistency condition for the components of the solution (here the velocity and the pressure) of the DAE for the method to be robust.
In the present paper, the authors suggest an algorithm to evaluate the multivariate normal integrals under the supposition that the correlation matrix R is quasi-decomposable, in which we have rij = aiaj for most i, j...
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In the present paper, the authors suggest an algorithm to evaluate the multivariate normal integrals under the supposition that the correlation matrix R is quasi-decomposable, in which we have rij = aiaj for most i, j, and rij = aiaj + bij for the others, where bij’s are the nonzero deviations. The algorithm makes the high-dimensional normal distribution reduce to a 2-dimensional or 3-dimensional integral which can be evaluated by the numerical method with a high *** supposition is close to what we encounter in practice. When correlation matrix is arbitrary, we suggest an approximate algorithm with a medium precision, it is, in general, better than some approximate algorithms. The simulation results of about 20000 high-dimensional integrals showed that the present algorithms were very efficient.
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